James, who scored 19 points on 6 of 18 shooting during Thursday's game, said the new NBA uniforms worn by both teams during the game have short sleeves and may have affected his performance, the South Florida Sun Sentinel reported Friday.
"I'm not making excuses," James said. "I'm not a big fan of the jerseys, not a big fan of them. I've got to figure something out the next time I wear the short-sleeved jerseys."
James said the tight fit of the jerseys, which the Heat will not have to wear for the rest of the season, affected his jump shot.
"I already don't have much room for error on my jumpers," James said.
James' complaints were echoed on the other side of the court by Spurs players Manu Ginobili and Kawhi Leonard. Giniboli said he wore a uniform a size too large for him for extra comfort.
"I got a bigger size," Ginobili said. "In the morning, I went to shoot and I felt it was a little tight ... In my case, the size I usually play with it, I had to bump one more because I need the freedom. I'm not used to playing with braces, pads, stuff like that."
Leonard said the jerseys are "just something I'm not used to. Just felt a little tight."